(a),Expand and simplify (n, summation,r=1) [T(r+1)-T(r)].
(b),Using the result of (a),find the value of (24,summation,r=1) [(√r+1)-√r].
answers:(a).T(n+1)-T(1) , (b).4
How can take that??
summation??
2007-05-29 7:17 pm
回答 (1)
2007-05-29 7:34 pm
✔ 最佳答案
first of all, T(r) is a function of r, and can take any form.(a)
= T(n+1)-T(n)
+T(n)-T(n-1)
+T(n-1)-T(n-2)
+...
+T(3)-T(2)
+T(2)-T(1)
----------------------
terms cancel each other, so the answer is T(n+1)-T(1)
(b)
simple substitution:
put n=24
T(25)-T(1)
=sqrt(25)-sqrt(1)
=5-1
=4
收錄日期: 2021-04-12 19:51:21
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https://hk.answers.yahoo.com/question/index?qid=20070529000051KK01062